The calculated distance (air line) between Hang Hau and Yuen Long Kau Hui is approximately 18 miles respectively 28 kilometers.
By car or train, the actual journey to Yuen Long Kau Hui is certainly longer, as only the direct route (as the crow flies) between Hang Hau and Yuen Long Kau Hui has been calculated here.
Air line (approximately)
28 kilometers
15 nautical miles